Parallel processing of frame based data transfers

A frame based data transfer system comprising:

• a storage device with a serial attached small computer systems interface (SAS);
• a receive frame parser coupled to SAS interface, the receive frame parser to receive a frame from the storage device, to store framing information from the frame in a receive header queue, and to store an information unit from the frame in an information unit buffer;
• a receive frame processor coupled to the receive header queue, the receive frame processor to perform transport layer tasks including reading a transport layer task context as determined by a tag field in the framing information, to determine how to handle the frame from the transport layer task context and the framing information, generating a DMA descriptor, and storing an updated transport layer task context;
• and
• a direct memory access (DMA) engine coupled to the information unit buffer and the receive frame processor, the DMA engine to perform DMA tasks including reading a DMA task context, transferring the information unit to a destination memory by processing the DMA descriptor, and storing an updated DMA task context, wherein the DMA engine performs the DMA tasks and the receive frame processor performs the transport layer tasks concurrently with one another.

A method of transferring framed data comprising:

• performing a frame parsing task including
• receiving a frame from a link layer interface,
• storing framing information from the frame in a receive header queue, and
• storing an information unit from the frame in an information unit buffer;
• performing a transport layer task including
• reading a transport layer task context as determined by a tag field in the framing information,
• determining how to handle the frame from the transport layer task context and the framing information,
• generating a DMA descriptor, and
• storing an updated transport layer task context;
• and
• performing a direct memory access (DMA) task concurrently with the transport layer task, the DMA task including
• reading a DMA task context,
• transferring a previously stored second information unit to a destination memory by processing a previously generated second DMA descriptor, and
• storing an updated DMA task context.